一人公司，是指公司的出资全部属于单一股东的公司。我国《公司法》允许自然人或法人单独出资设立一人公司，而国有独资公司也可视为一人公司的一种特殊形式。合资公司是指公司的全部股份或出资是属于两个或两个以上股东的公司。

通过检索可发现“一人公司”常见的译法有两种：one person company和sole proprietorship。虽然二者都可以表达“一人公司”，但是也存在一定的区别，所以使用时，要根据具体语境，可以从二者的本质含义上作区分，如下：

One person company

One person company (OPC) means a company formed with only one (single) person as a member, unlike the traditional manner of having at least two members.

On the basis of ownership, a company can be of three types: 1. One Person Company 2. Private Company 3. Public Company. The Companies Act, of 2013, introduced a number of ideas that had never before been used in Indian corporate law. One such major shift was the emergence of the one-person company concept. Before the new Companies Act was passed in 2013, several other nations had previously acknowledged the capability of people to create a corporation. China, Singapore, the UK, Australia, and the USA were a few of these.

One Person Business (OPC) is officially a company with only one shareholder, as its member are recognized as the company’s shareholders. OPCs often develop when there is just one founder or promoter of the company. Due to the multiple benefits that OPCs provide, businessmen or entreprenerd, who are just starting a business, choose this form of business over sole proprietorships.

Sole proprietorship

A sole proprietorship is an unincorporated business that has just one owner who pays personal income tax on profits earned from the business. Many sole proprietors do business under their own names because creating a separate business or trade name isn’t necessary.

Also referred to as a sole trader or a proprietorship, a sole proprietorship is the easiest type of business to establish or take apart, due to a lack of government regulation. As such, they are very popular among sole owners of businesses, individual self-contractors, and consultants. Most small businesses start as sole proprietorships and either stay that way or expand and transition to a limited liability entity or corporation.

If you want to start a one-owner business, the simplest and fastest way is through a sole proprietorship. Sole proprietorship begins when you begin conducting business. It doesn’t require filing federal or state forms and has few regulatory burdens, making it an ideal way for self-employed people to start out.

A sole proprietorship is very different from a corporation, a limited liability company (LLC), or a limited liability partnership (LLP), in that no separate legal entity is created. As a result, the business owner of a sole proprietorship is not exempt from liabilities incurred by the entity.

For example, the debts of the sole proprietorship are also the debts of the owner. However, the profits of the sole proprietorship are also the profits of the owner, as all profits flow directly to the business owner.

参考：

1. https://economictimes.indiatimes.com/small-biz/legal/the-one-man-show-understanding-the-concept-of-one-person-company/articleshow/72195134.cms?from=mdr

2. https://www.investopedia.com/terms/s/soleproprietorship.asp

3. https://baike.baidu.com/item/%E4%B8%80%E4%BA%BA%E5%85%AC%E5%8F%B8/1632042